[RFC,v5,6/7] kvmppc: Support reset of secure guest
diff mbox series

Message ID 20190709102545.9187-7-bharata@linux.ibm.com
State Superseded
Headers show
Series
  • kvmppc: HMM driver to manage pages of secure guest
Related show

Commit Message

Bharata B Rao July 9, 2019, 10:25 a.m. UTC
Add support for reset of secure guest via a new ioctl KVM_PPC_SVM_OFF.
This ioctl will be issued by QEMU during reset and includes the
the following steps:

- Ask UV to terminate the guest via UV_SVM_TERMINATE ucall
- Unpin the VPA pages so that they can be migrated back to secure
  side when guest becomes secure again. This is required because
  pinned pages can't be migrated.
- Reinitialize guest's partitioned scoped page tables. These are
  freed when guest become secure (H_SVM_INIT_DONE)
- Release all HMM pages of the secure guest.

After these steps, guest is ready to issue UV_ESM call once again
to switch to secure mode.

Signed-off-by: Bharata B Rao <bharata@linux.ibm.com>
Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
	[Implementation of uv_svm_terminate() and its call from
	guest shutdown path]
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
	[Unpinning of VPA pages]
---
 Documentation/virtual/kvm/api.txt         | 19 ++++++
 arch/powerpc/include/asm/kvm_book3s_hmm.h |  7 +++
 arch/powerpc/include/asm/kvm_ppc.h        |  2 +
 arch/powerpc/include/asm/ultravisor-api.h |  1 +
 arch/powerpc/include/asm/ultravisor.h     |  7 +++
 arch/powerpc/kvm/book3s_hv.c              | 70 +++++++++++++++++++++++
 arch/powerpc/kvm/book3s_hv_hmm.c          | 60 +++++++++++++++++++
 arch/powerpc/kvm/powerpc.c                | 12 ++++
 include/uapi/linux/kvm.h                  |  1 +
 tools/include/uapi/linux/kvm.h            |  1 +
 10 files changed, 180 insertions(+)

Comments

janani July 10, 2019, 1:30 p.m. UTC | #1
On 2019-07-09 05:25, Bharata B Rao wrote:
> Add support for reset of secure guest via a new ioctl KVM_PPC_SVM_OFF.
> This ioctl will be issued by QEMU during reset and includes the
> the following steps:
> 
> - Ask UV to terminate the guest via UV_SVM_TERMINATE ucall
> - Unpin the VPA pages so that they can be migrated back to secure
>   side when guest becomes secure again. This is required because
>   pinned pages can't be migrated.
> - Reinitialize guest's partitioned scoped page tables. These are
>   freed when guest become secure (H_SVM_INIT_DONE)
> - Release all HMM pages of the secure guest.
> 
> After these steps, guest is ready to issue UV_ESM call once again
> to switch to secure mode.
> 
> Signed-off-by: Bharata B Rao <bharata@linux.ibm.com>
> Signed-off-by: Sukadev Bhattiprolu <sukadev@linux.vnet.ibm.com>
> 	[Implementation of uv_svm_terminate() and its call from
> 	guest shutdown path]
> Signed-off-by: Ram Pai <linuxram@us.ibm.com>
> 	[Unpinning of VPA pages]
  Reviewed-by: Janani Janakiraman <janani@linux.ibm.com>
> ---
>  Documentation/virtual/kvm/api.txt         | 19 ++++++
>  arch/powerpc/include/asm/kvm_book3s_hmm.h |  7 +++
>  arch/powerpc/include/asm/kvm_ppc.h        |  2 +
>  arch/powerpc/include/asm/ultravisor-api.h |  1 +
>  arch/powerpc/include/asm/ultravisor.h     |  7 +++
>  arch/powerpc/kvm/book3s_hv.c              | 70 +++++++++++++++++++++++
>  arch/powerpc/kvm/book3s_hv_hmm.c          | 60 +++++++++++++++++++
>  arch/powerpc/kvm/powerpc.c                | 12 ++++
>  include/uapi/linux/kvm.h                  |  1 +
>  tools/include/uapi/linux/kvm.h            |  1 +
>  10 files changed, 180 insertions(+)
> 
> diff --git a/Documentation/virtual/kvm/api.txt
> b/Documentation/virtual/kvm/api.txt
> index ba6c42c576dd..c89c24ad86ed 100644
> --- a/Documentation/virtual/kvm/api.txt
> +++ b/Documentation/virtual/kvm/api.txt
> @@ -4065,6 +4065,25 @@ KVM_ARM_VCPU_FINALIZE call.
>  See KVM_ARM_VCPU_INIT for details of vcpu features that require 
> finalization
>  using this ioctl.
> 
> +4.120 KVM_PPC_SVM_OFF
> +
> +Capability: basic
> +Architectures: powerpc
> +Type: vm ioctl
> +Parameters: none
> +Returns: 0 on successful completion,
> +Errors:
> +  EINVAL:    if ultravisor failed to terminate the secure guest
> +  ENOMEM:    if hypervisor failed to allocate new radix page tables 
> for guest
> +
> +This ioctl is used to turn off the secure mode of the guest or 
> transition
> +the guest from secure mode to normal mode. This is invoked when the 
> guest
> +is reset. This has no effect if called for a normal guest.
> +
> +This ioctl issues an ultravisor call to terminate the secure guest,
> +unpin the VPA pages, reinitialize guest's partition scoped page
> +tables and releases all the HMM pages that is associated with this 
> guest.
> +
>  5. The kvm_run structure
>  ------------------------
> 
> diff --git a/arch/powerpc/include/asm/kvm_book3s_hmm.h
> b/arch/powerpc/include/asm/kvm_book3s_hmm.h
> index 8c7aacabb2e0..cd2b0f927766 100644
> --- a/arch/powerpc/include/asm/kvm_book3s_hmm.h
> +++ b/arch/powerpc/include/asm/kvm_book3s_hmm.h
> @@ -13,6 +13,8 @@ extern unsigned long kvmppc_h_svm_page_out(struct kvm 
> *kvm,
>  					  unsigned long page_shift);
>  extern unsigned long kvmppc_h_svm_init_start(struct kvm *kvm);
>  extern unsigned long kvmppc_h_svm_init_done(struct kvm *kvm);
> +extern void kvmppc_hmm_free_memslot_pfns(struct kvm *kvm,
> +		struct kvm_memslots *slots);
>  #else
>  static inline unsigned long
>  kvmppc_h_svm_page_in(struct kvm *kvm, unsigned long gra,
> @@ -37,5 +39,10 @@ static inline unsigned long
> kvmppc_h_svm_init_done(struct kvm *kvm)
>  {
>  	return H_UNSUPPORTED;
>  }
> +
> +static inline void kvmppc_hmm_free_memslot_pfns(struct kvm *kvm,
> +		struct kvm_memslots *slots)
> +{
> +}
>  #endif /* CONFIG_PPC_UV */
>  #endif /* __POWERPC_KVM_PPC_HMM_H__ */
> diff --git a/arch/powerpc/include/asm/kvm_ppc.h
> b/arch/powerpc/include/asm/kvm_ppc.h
> index bc892380e6cd..d80ece28d65d 100644
> --- a/arch/powerpc/include/asm/kvm_ppc.h
> +++ b/arch/powerpc/include/asm/kvm_ppc.h
> @@ -188,6 +188,7 @@ extern void
> kvm_spapr_tce_release_iommu_group(struct kvm *kvm,
>  extern int kvmppc_switch_mmu_to_hpt(struct kvm *kvm);
>  extern int kvmppc_switch_mmu_to_radix(struct kvm *kvm);
>  extern void kvmppc_setup_partition_table(struct kvm *kvm);
> +extern int kvmppc_reinit_partition_table(struct kvm *kvm);
> 
>  extern long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm,
>  				struct kvm_create_spapr_tce_64 *args);
> @@ -332,6 +333,7 @@ struct kvmppc_ops {
>  			       int size);
>  	int (*store_to_eaddr)(struct kvm_vcpu *vcpu, ulong *eaddr, void *ptr,
>  			      int size);
> +	int (*svm_off)(struct kvm *kvm);
>  };
> 
>  extern struct kvmppc_ops *kvmppc_hv_ops;
> diff --git a/arch/powerpc/include/asm/ultravisor-api.h
> b/arch/powerpc/include/asm/ultravisor-api.h
> index 9f5510b55892..c8180427fa01 100644
> --- a/arch/powerpc/include/asm/ultravisor-api.h
> +++ b/arch/powerpc/include/asm/ultravisor-api.h
> @@ -25,5 +25,6 @@
>  #define UV_PAGE_IN			0xF128
>  #define UV_PAGE_OUT			0xF12C
>  #define UV_PAGE_INVAL			0xF138
> +#define UV_SVM_TERMINATE		0xF13C
> 
>  #endif /* _ASM_POWERPC_ULTRAVISOR_API_H */
> diff --git a/arch/powerpc/include/asm/ultravisor.h
> b/arch/powerpc/include/asm/ultravisor.h
> index f4f674794b35..a5e4516c8ddb 100644
> --- a/arch/powerpc/include/asm/ultravisor.h
> +++ b/arch/powerpc/include/asm/ultravisor.h
> @@ -84,6 +84,13 @@ static inline int uv_page_inval(u64 lpid, u64 gpa,
> u64 page_shift)
> 
>  	return ucall(UV_PAGE_INVAL, retbuf, lpid, gpa, page_shift);
>  }
> +
> +static inline int uv_svm_terminate(u64 lpid)
> +{
> +	unsigned long retbuf[UCALL_BUFSIZE];
> +
> +	return ucall(UV_SVM_TERMINATE, retbuf, lpid);
> +}
>  #endif /* !__ASSEMBLY__ */
> 
>  #endif	/* _ASM_POWERPC_ULTRAVISOR_H */
> diff --git a/arch/powerpc/kvm/book3s_hv.c 
> b/arch/powerpc/kvm/book3s_hv.c
> index 7cbb5edaed01..41b0fff199d3 100644
> --- a/arch/powerpc/kvm/book3s_hv.c
> +++ b/arch/powerpc/kvm/book3s_hv.c
> @@ -2437,6 +2437,15 @@ static void unpin_vpa(struct kvm *kvm, struct
> kvmppc_vpa *vpa)
>  					vpa->dirty);
>  }
> 
> +static void unpin_vpa_reset(struct kvm *kvm, struct kvmppc_vpa *vpa)
> +{
> +	unpin_vpa(kvm, vpa);
> +	vpa->gpa = 0;
> +	vpa->pinned_addr = NULL;
> +	vpa->dirty = false;
> +	vpa->update_pending = 0;
> +}
> +
>  static void kvmppc_core_vcpu_free_hv(struct kvm_vcpu *vcpu)
>  {
>  	spin_lock(&vcpu->arch.vpa_update_lock);
> @@ -4577,6 +4586,22 @@ void kvmppc_setup_partition_table(struct kvm 
> *kvm)
>  	kvmhv_set_ptbl_entry(kvm->arch.lpid, dw0, dw1);
>  }
> 
> +/*
> + * Called from KVM_PPC_SVM_OFF ioctl at guest reset time when secure
> + * guest is converted back to normal guest.
> + */
> +int kvmppc_reinit_partition_table(struct kvm *kvm)
> +{
> +	int ret;
> +
> +	ret = kvmppc_init_vm_radix(kvm);
> +	if (ret)
> +		return ret;
> +
> +	kvmppc_setup_partition_table(kvm);
> +	return 0;
> +}
> +
>  /*
>   * Set up HPT (hashed page table) and RMA (real-mode area).
>   * Must be called with kvm->lock held.
> @@ -4956,6 +4981,7 @@ static void kvmppc_core_destroy_vm_hv(struct kvm 
> *kvm)
>  		if (nesting_enabled(kvm))
>  			kvmhv_release_all_nested(kvm);
>  		kvm->arch.process_table = 0;
> +		uv_svm_terminate(kvm->arch.lpid);
>  		kvmhv_set_ptbl_entry(kvm->arch.lpid, 0, 0);
>  	}
>  	kvmppc_free_lpid(kvm->arch.lpid);
> @@ -5397,6 +5423,49 @@ static int kvmhv_store_to_eaddr(struct kvm_vcpu
> *vcpu, ulong *eaddr, void *ptr,
>  	return rc;
>  }
> 
> +/*
> + *  IOCTL handler to turn off secure mode of guest
> + *
> + * - Issue ucall to terminate the guest on the UV side
> + * - Unpin the VPA pages (Enables these pages to be migrated back
> + *   when VM becomes secure again)
> + * - Recreate partition table as the guest is transitioning back to
> + *   normal mode
> + * - Release all HMM pages
> + */
> +static int kvmhv_svm_off(struct kvm *kvm)
> +{
> +	struct kvm_vcpu *vcpu;
> +	int ret = 0;
> +	int i;
> +
> +	if (kvmppc_is_guest_secure(kvm)) {
> +		ret = uv_svm_terminate(kvm->arch.lpid);
> +		if (ret != U_SUCCESS) {
> +			ret = -EINVAL;
> +			goto out;
> +		}
> +
> +		kvm_for_each_vcpu(i, vcpu, kvm) {
> +			spin_lock(&vcpu->arch.vpa_update_lock);
> +			unpin_vpa_reset(kvm, &vcpu->arch.dtl);
> +			unpin_vpa_reset(kvm, &vcpu->arch.slb_shadow);
> +			unpin_vpa_reset(kvm, &vcpu->arch.vpa);
> +			spin_unlock(&vcpu->arch.vpa_update_lock);
> +		}
> +
> +		ret = kvmppc_reinit_partition_table(kvm);
> +		if (ret)
> +			goto out;
> +		kvm->arch.secure_guest = 0;
> +		for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++)
> +			kvmppc_hmm_free_memslot_pfns(kvm,
> +			__kvm_memslots(kvm, i));
> +	}
> +out:
> +	return ret;
> +}
> +
>  static struct kvmppc_ops kvm_ops_hv = {
>  	.get_sregs = kvm_arch_vcpu_ioctl_get_sregs_hv,
>  	.set_sregs = kvm_arch_vcpu_ioctl_set_sregs_hv,
> @@ -5439,6 +5508,7 @@ static struct kvmppc_ops kvm_ops_hv = {
>  	.enable_nested = kvmhv_enable_nested,
>  	.load_from_eaddr = kvmhv_load_from_eaddr,
>  	.store_to_eaddr = kvmhv_store_to_eaddr,
> +	.svm_off = kvmhv_svm_off,
>  };
> 
>  static int kvm_init_subcore_bitmap(void)
> diff --git a/arch/powerpc/kvm/book3s_hv_hmm.c 
> b/arch/powerpc/kvm/book3s_hv_hmm.c
> index 9e6c88de456f..165926c069ba 100644
> --- a/arch/powerpc/kvm/book3s_hv_hmm.c
> +++ b/arch/powerpc/kvm/book3s_hv_hmm.c
> @@ -38,6 +38,8 @@
>  #include <linux/kvm_host.h>
>  #include <linux/sched/mm.h>
>  #include <asm/ultravisor.h>
> +#include <asm/kvm_ppc.h>
> +#include <asm/kvm_book3s.h>
> 
>  struct kvmppc_hmm_device {
>  	struct hmm_device *device;
> @@ -98,6 +100,12 @@ unsigned long kvmppc_h_svm_init_done(struct kvm 
> *kvm)
>  		return H_UNSUPPORTED;
> 
>  	kvm->arch.secure_guest |= KVMPPC_SECURE_INIT_DONE;
> +	if (kvm_is_radix(kvm)) {
> +		pr_info("LPID %d went secure, freeing HV side radix pgtables\n",
> +			kvm->arch.lpid);
> +		kvmppc_free_radix(kvm);
> +	}
> +
>  	return H_SUCCESS;
>  }
> 
> @@ -113,6 +121,58 @@ static inline bool kvmppc_is_hmm_pfn(unsigned long 
> pfn)
>  	return !!(pfn & KVMPPC_PFN_HMM);
>  }
> 
> +/*
> + * Drop HMM pages that we maintain for the secure guest
> + *
> + * We mark the pages to be skipped from UV_PAGE_OUT when there is HMM
> + * fault on these pages. Next we get these pages, force HMM fault,
> + * do fault migration to replace the HMM PTEs from QEMU page tables
> + * with normal PTEs from newly allocated pages.
> + */
> +static void kvmppc_hmm_drop_pages(struct kvm_memory_slot *free,
> struct kvm *kvm)
> +{
> +	int i;
> +	struct kvmppc_hmm_page_pvt *pvt;
> +	unsigned long pfn;
> +
> +	for (i = 0; i < free->npages; i++) {
> +		unsigned long *rmap = &free->arch.rmap[i];
> +		struct page *hmm_page;
> +
> +		if (kvmppc_is_hmm_pfn(*rmap)) {
> +			hmm_page = pfn_to_page(*rmap & ~KVMPPC_PFN_HMM);
> +			pvt = (struct kvmppc_hmm_page_pvt *)
> +				hmm_devmem_page_get_drvdata(hmm_page);
> +			pvt->skip_page_out = true;
> +
> +			pfn = gfn_to_pfn(kvm, pvt->gpa >> PAGE_SHIFT);
> +			if (is_error_noslot_pfn(pfn))
> +				continue;
> +			kvm_release_pfn_clean(pfn);
> +		}
> +	}
> +}
> +
> +/*
> + * Called from KVM_PPC_SVM_OFF ioctl when secure guest is reset
> + *
> + * UV has already cleaned up the guest, we release any HMM pages that
> + * we maintain
> + */
> +void kvmppc_hmm_free_memslot_pfns(struct kvm *kvm, struct kvm_memslots 
> *slots)
> +{
> +	struct kvm_memory_slot *memslot;
> +	int srcu_idx;
> +
> +	if (!slots)
> +		return;
> +
> +	srcu_idx = srcu_read_lock(&kvm->srcu);
> +	kvm_for_each_memslot(memslot, slots)
> +		kvmppc_hmm_drop_pages(memslot, kvm);
> +	srcu_read_unlock(&kvm->srcu, srcu_idx);
> +}
> +
>  /*
>   * Get a free HMM PFN from the pool
>   *
> diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
> index 3393b166817a..0c5fae004adf 100644
> --- a/arch/powerpc/kvm/powerpc.c
> +++ b/arch/powerpc/kvm/powerpc.c
> @@ -42,6 +42,8 @@
>  #include <asm/hvcall.h>
>  #include <asm/plpar_wrappers.h>
>  #endif
> +#include <asm/ultravisor.h>
> +#include <asm/kvm_host.h>
> 
>  #include "timing.h"
>  #include "irq.h"
> @@ -2423,6 +2425,16 @@ long kvm_arch_vm_ioctl(struct file *filp,
>  			r = -EFAULT;
>  		break;
>  	}
> +	case KVM_PPC_SVM_OFF: {
> +		struct kvm *kvm = filp->private_data;
> +
> +		r = 0;
> +		if (!kvm->arch.kvm_ops->svm_off)
> +			goto out;
> +
> +		r = kvm->arch.kvm_ops->svm_off(kvm);
> +		break;
> +	}
>  	default: {
>  		struct kvm *kvm = filp->private_data;
>  		r = kvm->arch.kvm_ops->arch_vm_ioctl(filp, ioctl, arg);
> diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
> index 2fe12b40d503..c1dbdd428025 100644
> --- a/include/uapi/linux/kvm.h
> +++ b/include/uapi/linux/kvm.h
> @@ -1327,6 +1327,7 @@ struct kvm_s390_ucas_mapping {
>  #define KVM_PPC_GET_RMMU_INFO	  _IOW(KVMIO,  0xb0, struct 
> kvm_ppc_rmmu_info)
>  /* Available with KVM_CAP_PPC_GET_CPU_CHAR */
>  #define KVM_PPC_GET_CPU_CHAR	  _IOR(KVMIO,  0xb1, struct 
> kvm_ppc_cpu_char)
> +#define KVM_PPC_SVM_OFF		  _IO(KVMIO,  0xb2)
> 
>  /* ioctl for vm fd */
>  #define KVM_CREATE_DEVICE	  _IOWR(KVMIO,  0xe0, struct 
> kvm_create_device)
> diff --git a/tools/include/uapi/linux/kvm.h 
> b/tools/include/uapi/linux/kvm.h
> index 6d4ea4b6c922..03c89f4a01b2 100644
> --- a/tools/include/uapi/linux/kvm.h
> +++ b/tools/include/uapi/linux/kvm.h
> @@ -1319,6 +1319,7 @@ struct kvm_s390_ucas_mapping {
>  #define KVM_PPC_GET_RMMU_INFO	  _IOW(KVMIO,  0xb0, struct 
> kvm_ppc_rmmu_info)
>  /* Available with KVM_CAP_PPC_GET_CPU_CHAR */
>  #define KVM_PPC_GET_CPU_CHAR	  _IOR(KVMIO,  0xb1, struct 
> kvm_ppc_cpu_char)
> +#define KVM_PPC_SVM_OFF		  _IO(KVMIO,  0xb2)
> 
>  /* ioctl for vm fd */
>  #define KVM_CREATE_DEVICE	  _IOWR(KVMIO,  0xe0, struct 
> kvm_create_device)

Patch
diff mbox series

diff --git a/Documentation/virtual/kvm/api.txt b/Documentation/virtual/kvm/api.txt
index ba6c42c576dd..c89c24ad86ed 100644
--- a/Documentation/virtual/kvm/api.txt
+++ b/Documentation/virtual/kvm/api.txt
@@ -4065,6 +4065,25 @@  KVM_ARM_VCPU_FINALIZE call.
 See KVM_ARM_VCPU_INIT for details of vcpu features that require finalization
 using this ioctl.
 
+4.120 KVM_PPC_SVM_OFF
+
+Capability: basic
+Architectures: powerpc
+Type: vm ioctl
+Parameters: none
+Returns: 0 on successful completion,
+Errors:
+  EINVAL:    if ultravisor failed to terminate the secure guest
+  ENOMEM:    if hypervisor failed to allocate new radix page tables for guest
+
+This ioctl is used to turn off the secure mode of the guest or transition
+the guest from secure mode to normal mode. This is invoked when the guest
+is reset. This has no effect if called for a normal guest.
+
+This ioctl issues an ultravisor call to terminate the secure guest,
+unpin the VPA pages, reinitialize guest's partition scoped page
+tables and releases all the HMM pages that is associated with this guest.
+
 5. The kvm_run structure
 ------------------------
 
diff --git a/arch/powerpc/include/asm/kvm_book3s_hmm.h b/arch/powerpc/include/asm/kvm_book3s_hmm.h
index 8c7aacabb2e0..cd2b0f927766 100644
--- a/arch/powerpc/include/asm/kvm_book3s_hmm.h
+++ b/arch/powerpc/include/asm/kvm_book3s_hmm.h
@@ -13,6 +13,8 @@  extern unsigned long kvmppc_h_svm_page_out(struct kvm *kvm,
 					  unsigned long page_shift);
 extern unsigned long kvmppc_h_svm_init_start(struct kvm *kvm);
 extern unsigned long kvmppc_h_svm_init_done(struct kvm *kvm);
+extern void kvmppc_hmm_free_memslot_pfns(struct kvm *kvm,
+		struct kvm_memslots *slots);
 #else
 static inline unsigned long
 kvmppc_h_svm_page_in(struct kvm *kvm, unsigned long gra,
@@ -37,5 +39,10 @@  static inline unsigned long kvmppc_h_svm_init_done(struct kvm *kvm)
 {
 	return H_UNSUPPORTED;
 }
+
+static inline void kvmppc_hmm_free_memslot_pfns(struct kvm *kvm,
+		struct kvm_memslots *slots)
+{
+}
 #endif /* CONFIG_PPC_UV */
 #endif /* __POWERPC_KVM_PPC_HMM_H__ */
diff --git a/arch/powerpc/include/asm/kvm_ppc.h b/arch/powerpc/include/asm/kvm_ppc.h
index bc892380e6cd..d80ece28d65d 100644
--- a/arch/powerpc/include/asm/kvm_ppc.h
+++ b/arch/powerpc/include/asm/kvm_ppc.h
@@ -188,6 +188,7 @@  extern void kvm_spapr_tce_release_iommu_group(struct kvm *kvm,
 extern int kvmppc_switch_mmu_to_hpt(struct kvm *kvm);
 extern int kvmppc_switch_mmu_to_radix(struct kvm *kvm);
 extern void kvmppc_setup_partition_table(struct kvm *kvm);
+extern int kvmppc_reinit_partition_table(struct kvm *kvm);
 
 extern long kvm_vm_ioctl_create_spapr_tce(struct kvm *kvm,
 				struct kvm_create_spapr_tce_64 *args);
@@ -332,6 +333,7 @@  struct kvmppc_ops {
 			       int size);
 	int (*store_to_eaddr)(struct kvm_vcpu *vcpu, ulong *eaddr, void *ptr,
 			      int size);
+	int (*svm_off)(struct kvm *kvm);
 };
 
 extern struct kvmppc_ops *kvmppc_hv_ops;
diff --git a/arch/powerpc/include/asm/ultravisor-api.h b/arch/powerpc/include/asm/ultravisor-api.h
index 9f5510b55892..c8180427fa01 100644
--- a/arch/powerpc/include/asm/ultravisor-api.h
+++ b/arch/powerpc/include/asm/ultravisor-api.h
@@ -25,5 +25,6 @@ 
 #define UV_PAGE_IN			0xF128
 #define UV_PAGE_OUT			0xF12C
 #define UV_PAGE_INVAL			0xF138
+#define UV_SVM_TERMINATE		0xF13C
 
 #endif /* _ASM_POWERPC_ULTRAVISOR_API_H */
diff --git a/arch/powerpc/include/asm/ultravisor.h b/arch/powerpc/include/asm/ultravisor.h
index f4f674794b35..a5e4516c8ddb 100644
--- a/arch/powerpc/include/asm/ultravisor.h
+++ b/arch/powerpc/include/asm/ultravisor.h
@@ -84,6 +84,13 @@  static inline int uv_page_inval(u64 lpid, u64 gpa, u64 page_shift)
 
 	return ucall(UV_PAGE_INVAL, retbuf, lpid, gpa, page_shift);
 }
+
+static inline int uv_svm_terminate(u64 lpid)
+{
+	unsigned long retbuf[UCALL_BUFSIZE];
+
+	return ucall(UV_SVM_TERMINATE, retbuf, lpid);
+}
 #endif /* !__ASSEMBLY__ */
 
 #endif	/* _ASM_POWERPC_ULTRAVISOR_H */
diff --git a/arch/powerpc/kvm/book3s_hv.c b/arch/powerpc/kvm/book3s_hv.c
index 7cbb5edaed01..41b0fff199d3 100644
--- a/arch/powerpc/kvm/book3s_hv.c
+++ b/arch/powerpc/kvm/book3s_hv.c
@@ -2437,6 +2437,15 @@  static void unpin_vpa(struct kvm *kvm, struct kvmppc_vpa *vpa)
 					vpa->dirty);
 }
 
+static void unpin_vpa_reset(struct kvm *kvm, struct kvmppc_vpa *vpa)
+{
+	unpin_vpa(kvm, vpa);
+	vpa->gpa = 0;
+	vpa->pinned_addr = NULL;
+	vpa->dirty = false;
+	vpa->update_pending = 0;
+}
+
 static void kvmppc_core_vcpu_free_hv(struct kvm_vcpu *vcpu)
 {
 	spin_lock(&vcpu->arch.vpa_update_lock);
@@ -4577,6 +4586,22 @@  void kvmppc_setup_partition_table(struct kvm *kvm)
 	kvmhv_set_ptbl_entry(kvm->arch.lpid, dw0, dw1);
 }
 
+/*
+ * Called from KVM_PPC_SVM_OFF ioctl at guest reset time when secure
+ * guest is converted back to normal guest.
+ */
+int kvmppc_reinit_partition_table(struct kvm *kvm)
+{
+	int ret;
+
+	ret = kvmppc_init_vm_radix(kvm);
+	if (ret)
+		return ret;
+
+	kvmppc_setup_partition_table(kvm);
+	return 0;
+}
+
 /*
  * Set up HPT (hashed page table) and RMA (real-mode area).
  * Must be called with kvm->lock held.
@@ -4956,6 +4981,7 @@  static void kvmppc_core_destroy_vm_hv(struct kvm *kvm)
 		if (nesting_enabled(kvm))
 			kvmhv_release_all_nested(kvm);
 		kvm->arch.process_table = 0;
+		uv_svm_terminate(kvm->arch.lpid);
 		kvmhv_set_ptbl_entry(kvm->arch.lpid, 0, 0);
 	}
 	kvmppc_free_lpid(kvm->arch.lpid);
@@ -5397,6 +5423,49 @@  static int kvmhv_store_to_eaddr(struct kvm_vcpu *vcpu, ulong *eaddr, void *ptr,
 	return rc;
 }
 
+/*
+ *  IOCTL handler to turn off secure mode of guest
+ *
+ * - Issue ucall to terminate the guest on the UV side
+ * - Unpin the VPA pages (Enables these pages to be migrated back
+ *   when VM becomes secure again)
+ * - Recreate partition table as the guest is transitioning back to
+ *   normal mode
+ * - Release all HMM pages
+ */
+static int kvmhv_svm_off(struct kvm *kvm)
+{
+	struct kvm_vcpu *vcpu;
+	int ret = 0;
+	int i;
+
+	if (kvmppc_is_guest_secure(kvm)) {
+		ret = uv_svm_terminate(kvm->arch.lpid);
+		if (ret != U_SUCCESS) {
+			ret = -EINVAL;
+			goto out;
+		}
+
+		kvm_for_each_vcpu(i, vcpu, kvm) {
+			spin_lock(&vcpu->arch.vpa_update_lock);
+			unpin_vpa_reset(kvm, &vcpu->arch.dtl);
+			unpin_vpa_reset(kvm, &vcpu->arch.slb_shadow);
+			unpin_vpa_reset(kvm, &vcpu->arch.vpa);
+			spin_unlock(&vcpu->arch.vpa_update_lock);
+		}
+
+		ret = kvmppc_reinit_partition_table(kvm);
+		if (ret)
+			goto out;
+		kvm->arch.secure_guest = 0;
+		for (i = 0; i < KVM_ADDRESS_SPACE_NUM; i++)
+			kvmppc_hmm_free_memslot_pfns(kvm,
+			__kvm_memslots(kvm, i));
+	}
+out:
+	return ret;
+}
+
 static struct kvmppc_ops kvm_ops_hv = {
 	.get_sregs = kvm_arch_vcpu_ioctl_get_sregs_hv,
 	.set_sregs = kvm_arch_vcpu_ioctl_set_sregs_hv,
@@ -5439,6 +5508,7 @@  static struct kvmppc_ops kvm_ops_hv = {
 	.enable_nested = kvmhv_enable_nested,
 	.load_from_eaddr = kvmhv_load_from_eaddr,
 	.store_to_eaddr = kvmhv_store_to_eaddr,
+	.svm_off = kvmhv_svm_off,
 };
 
 static int kvm_init_subcore_bitmap(void)
diff --git a/arch/powerpc/kvm/book3s_hv_hmm.c b/arch/powerpc/kvm/book3s_hv_hmm.c
index 9e6c88de456f..165926c069ba 100644
--- a/arch/powerpc/kvm/book3s_hv_hmm.c
+++ b/arch/powerpc/kvm/book3s_hv_hmm.c
@@ -38,6 +38,8 @@ 
 #include <linux/kvm_host.h>
 #include <linux/sched/mm.h>
 #include <asm/ultravisor.h>
+#include <asm/kvm_ppc.h>
+#include <asm/kvm_book3s.h>
 
 struct kvmppc_hmm_device {
 	struct hmm_device *device;
@@ -98,6 +100,12 @@  unsigned long kvmppc_h_svm_init_done(struct kvm *kvm)
 		return H_UNSUPPORTED;
 
 	kvm->arch.secure_guest |= KVMPPC_SECURE_INIT_DONE;
+	if (kvm_is_radix(kvm)) {
+		pr_info("LPID %d went secure, freeing HV side radix pgtables\n",
+			kvm->arch.lpid);
+		kvmppc_free_radix(kvm);
+	}
+
 	return H_SUCCESS;
 }
 
@@ -113,6 +121,58 @@  static inline bool kvmppc_is_hmm_pfn(unsigned long pfn)
 	return !!(pfn & KVMPPC_PFN_HMM);
 }
 
+/*
+ * Drop HMM pages that we maintain for the secure guest
+ *
+ * We mark the pages to be skipped from UV_PAGE_OUT when there is HMM
+ * fault on these pages. Next we get these pages, force HMM fault,
+ * do fault migration to replace the HMM PTEs from QEMU page tables
+ * with normal PTEs from newly allocated pages.
+ */
+static void kvmppc_hmm_drop_pages(struct kvm_memory_slot *free, struct kvm *kvm)
+{
+	int i;
+	struct kvmppc_hmm_page_pvt *pvt;
+	unsigned long pfn;
+
+	for (i = 0; i < free->npages; i++) {
+		unsigned long *rmap = &free->arch.rmap[i];
+		struct page *hmm_page;
+
+		if (kvmppc_is_hmm_pfn(*rmap)) {
+			hmm_page = pfn_to_page(*rmap & ~KVMPPC_PFN_HMM);
+			pvt = (struct kvmppc_hmm_page_pvt *)
+				hmm_devmem_page_get_drvdata(hmm_page);
+			pvt->skip_page_out = true;
+
+			pfn = gfn_to_pfn(kvm, pvt->gpa >> PAGE_SHIFT);
+			if (is_error_noslot_pfn(pfn))
+				continue;
+			kvm_release_pfn_clean(pfn);
+		}
+	}
+}
+
+/*
+ * Called from KVM_PPC_SVM_OFF ioctl when secure guest is reset
+ *
+ * UV has already cleaned up the guest, we release any HMM pages that
+ * we maintain
+ */
+void kvmppc_hmm_free_memslot_pfns(struct kvm *kvm, struct kvm_memslots *slots)
+{
+	struct kvm_memory_slot *memslot;
+	int srcu_idx;
+
+	if (!slots)
+		return;
+
+	srcu_idx = srcu_read_lock(&kvm->srcu);
+	kvm_for_each_memslot(memslot, slots)
+		kvmppc_hmm_drop_pages(memslot, kvm);
+	srcu_read_unlock(&kvm->srcu, srcu_idx);
+}
+
 /*
  * Get a free HMM PFN from the pool
  *
diff --git a/arch/powerpc/kvm/powerpc.c b/arch/powerpc/kvm/powerpc.c
index 3393b166817a..0c5fae004adf 100644
--- a/arch/powerpc/kvm/powerpc.c
+++ b/arch/powerpc/kvm/powerpc.c
@@ -42,6 +42,8 @@ 
 #include <asm/hvcall.h>
 #include <asm/plpar_wrappers.h>
 #endif
+#include <asm/ultravisor.h>
+#include <asm/kvm_host.h>
 
 #include "timing.h"
 #include "irq.h"
@@ -2423,6 +2425,16 @@  long kvm_arch_vm_ioctl(struct file *filp,
 			r = -EFAULT;
 		break;
 	}
+	case KVM_PPC_SVM_OFF: {
+		struct kvm *kvm = filp->private_data;
+
+		r = 0;
+		if (!kvm->arch.kvm_ops->svm_off)
+			goto out;
+
+		r = kvm->arch.kvm_ops->svm_off(kvm);
+		break;
+	}
 	default: {
 		struct kvm *kvm = filp->private_data;
 		r = kvm->arch.kvm_ops->arch_vm_ioctl(filp, ioctl, arg);
diff --git a/include/uapi/linux/kvm.h b/include/uapi/linux/kvm.h
index 2fe12b40d503..c1dbdd428025 100644
--- a/include/uapi/linux/kvm.h
+++ b/include/uapi/linux/kvm.h
@@ -1327,6 +1327,7 @@  struct kvm_s390_ucas_mapping {
 #define KVM_PPC_GET_RMMU_INFO	  _IOW(KVMIO,  0xb0, struct kvm_ppc_rmmu_info)
 /* Available with KVM_CAP_PPC_GET_CPU_CHAR */
 #define KVM_PPC_GET_CPU_CHAR	  _IOR(KVMIO,  0xb1, struct kvm_ppc_cpu_char)
+#define KVM_PPC_SVM_OFF		  _IO(KVMIO,  0xb2)
 
 /* ioctl for vm fd */
 #define KVM_CREATE_DEVICE	  _IOWR(KVMIO,  0xe0, struct kvm_create_device)
diff --git a/tools/include/uapi/linux/kvm.h b/tools/include/uapi/linux/kvm.h
index 6d4ea4b6c922..03c89f4a01b2 100644
--- a/tools/include/uapi/linux/kvm.h
+++ b/tools/include/uapi/linux/kvm.h
@@ -1319,6 +1319,7 @@  struct kvm_s390_ucas_mapping {
 #define KVM_PPC_GET_RMMU_INFO	  _IOW(KVMIO,  0xb0, struct kvm_ppc_rmmu_info)
 /* Available with KVM_CAP_PPC_GET_CPU_CHAR */
 #define KVM_PPC_GET_CPU_CHAR	  _IOR(KVMIO,  0xb1, struct kvm_ppc_cpu_char)
+#define KVM_PPC_SVM_OFF		  _IO(KVMIO,  0xb2)
 
 /* ioctl for vm fd */
 #define KVM_CREATE_DEVICE	  _IOWR(KVMIO,  0xe0, struct kvm_create_device)